How to encode the filename parameter of Content-Disposition header in HTTP?

Question

Web applications that want to force a resource to be downloaded rather than directly rendered in a Web browser issue a Content-Disposition hea

Answer 1

In PHP this did it for me (assuming the filename is UTF8 encoded):

header('Content-Disposition: attachment;'
    . 'filename="' . addslashes(utf8_decode($filename)) . '";'
    . 'filename*=utf-8\'\'' . rawurlencode($filename));

Tested against IE8-11, Firefox and Chrome.
If the browser can interpret filename*=utf-8 it will use the UTF8 version of the filename, else it will use the decoded filename. If your filename contains characters that can't be represented in ISO-8859-1 you might want to consider using iconv instead.